5 Why Analysis: Problem-Solving Simplified

The 5 Why analysis is a method for finding the root of a problem or situation. Japanese industrialists in the 20th century observed that asking ‘why’ five times iteratively is a good strategy for the production floor. 

Sakichi Toyoda introduced the 5 Why analysis in the 1930s. Taiichi Ohno considered it the scientific base of the Toyota Production System’s approach, and he later fine-tuned it for problem-solving training. Today, the 5 Why technique has gone beyond Toyota Motor Corporation and Japanese industrialism to Eric Reis's Lean Startup thinking. 

What is 5 Why Analysis?

The 5 Why analysis is a linear interrogative process for uncovering issues on the surface to get to the root of the problem. Asking one why after another successively creates a means to move deeper into relative contexts from where the problem originates. That helps in taking countermeasures for the symptoms uncovered. 

Why Use 5 Why Analysis

Some key benefits of the 5 Why analysis.

Beyond the Superficial 

This technique prevents a team from only looking at the surface-level symptoms. Looking at the top could lead to misunderstandings and assumptions that are never good for team morale. That leads to overall workplace inefficiency.  

As a useful troubleshooting process, it demands the team to ask why consecutively until they reach a conclusion. So, it makes it a collaborative effort. 

Can be Flexible

The 5 Why method is not complicated, and it does not require too much technical expertise. It is used along with various tools and industries where problems are simple to moderate. Over the years, this technique has been complementary to fishbone diagram, one of the major 7QC tools. Sometimes, it is also a fine addition to Kaizen. 

Where is 5 Why Analysis Used?

Let’s see how the 5 Why analysis is used in different industries. 

Identifying Quality Issues in Six Sigma

The 5 Whys method is among the most well-known root cause analysis techniques in Six Sigma. It especially helps in narrowing down quality issues during the ‘Analyse’ phase in the DMAIC cycle. 

Understanding Product Market Fit

The product-market fit is about understanding what customers expect. It can help identify the motivations behind customer preferences. Based on this, a minimal viable product can be built around. 

When to Use 5 Why Analysis?

Here are some instances where using the 5 Whys model is helpful. 

• Troubleshooting simple to moderate problems
• Identifying inefficiencies in processes
• Making decisions for product development
• Taking preventive measures on potential risks

When to Not Use the 5 Whys?

The 5 Why won’t be useful when problems face these conditions. 

• If there are multiple interconnected issues, it is an oversimplified approach that does not help.
• Industries like aerospace and healthcare cannot rely on this technique. There needs to be other advanced root cause analysis techniques like fault tree analysis or FMEA (Failure Mode and Effects Analysis). 

Example of 5 Whys Technique

Look at this example. 

Why	Answer
Why is the delivery of products delayed?	Because the delivery trucks often arrive late to the warehouse.
Why do the delivery trucks arrive late at the warehouse?	Because they get stuck in traffic on the highway.
Why is there heavy traffic on the highway?	Because of ongoing construction work.
Why is there ongoing construction work on the highway?	Because the city is upgrading the infrastructure to accommodate increased traffic flow.
Why is there an increase in traffic flow?	Because of the recent population growth in the city.

In this 5 why analysis example,

• The initial problem is the delayed product delivery.
• By asking "Why?" repeatedly, underlying issues were found. 
• The root cause of the delayed deliveries is the recent population growth in the city, which has led to increased traffic flow. Consequently, ongoing construction work results in traffic congestion and delays for delivery trucks.

How to Perform 5 Why Analysis

By now, performing the 5 Whys root cause analysis should be easy. Follow these steps. 

1. Identify the problem or issue that you want to address.
2. Phrase the question in a way that prompts deeper exploration.
3. Ask "why" again to dig deeper into the root cause. Continue this process iteratively, asking "why" up to five times or until you reach a point where further questioning doesn't provide meaningful insights.
4. Review the answers generated during the 5 Whys process to identify common themes or patterns.
5. Based on your analysis, determine the root cause or causes of the problem. 

5 Why Analysis Best Practices

Before conducting the five why analysis, here are some tips. 

• Maintain objectivity throughout the analysis process. Avoid placing blame or making subjective judgments.
• Follow a systematic approach to the 5 Whys analysis, such as documenting each "why" question and its corresponding answer.
• Be open to revisiting earlier answers or changing direction if new information emerges during the analysis.